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11+interest-growth

Interest defined

Explore why interest is the time-value of money.

In this lesson

Interest defined is part of What Is Interest?. This preview shows how interest-growth connects to everyday family decisions such as earning, saving, spending choices, goals, approvals, or parent-guided money conversations inside Progress Penguin.

Think about this money choice

Imagine this situation: You lend a friend 5000 in local currency for 3 months and they return 5500 in local currency.

How it works

Interest is the time-value of money. From the lender's perspective it is income; from the borrower's it is a cost. The same concept — just viewed from different sides.

Apply it to a real decision

Real-life money moment: You save 10000 in local currency at 8% per year. A friend borrows 10000 in local currency at 20% per year.

Activity preview

Connect the ideas

Use the lesson to complete this short practice activity.

Practice adding money to savings

Open Requests and make a deposit request into savings so you can see how saving starts. Parent approval can happen later.

Quiz preview

Interest is best described as:

The price of money over time
A tax as a reliable approach
A discount as a reliable approach
A type of fee in practical terms

You lend a friend 5000 in local currency for 3 months and they return 5500 in local currency. What is the 500 in local currency called and what percentage is it?

A fee for the inconvenience
Profit — only businesses earn interest
A gift — no financial name
Interest — 500 in local currency / 5000 in local currency = 10% for 3 months